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 A117980 Legendre-binomial transform of (-1)^n for p=3. 1
 1, 0, 3, 0, 0, 0, 3, 0, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 9, 0, 0, 0, 9, 0, 27, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 9, 0, 0, 0, 9, 0, 27, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9, 0, 27, 0, 0, 0, 27, 0, 81, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS a(n)=a(3n)=a(3n+2)/3; a(3n+2)=0. LINKS Antti Karttunen, Table of n, a(n) for n = 0..19683 FORMULA a(n)=sum{k=0..n, L(C(n,k)/3)*(-1)^k} where L(j/p) is the Legendre symbol of j and p. PROG (PARI) A117980(n) = sum(k=0, n, kronecker(binomial(n, k), 3)*((-1)^k)); \\ Antti Karttunen, Sep 20 2019 CROSSREFS Sequence in context: A219551 A200221 A158678 * A065032 A007514 A151671 Adjacent sequences:  A117977 A117978 A117979 * A117981 A117982 A117983 KEYWORD easy,nonn AUTHOR Paul Barry, Apr 06 2006 STATUS approved

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Last modified October 15 00:14 EDT 2019. Contains 328025 sequences. (Running on oeis4.)